This invention relates to junctions (which may also be termed xe2x80x9cfittingsxe2x80x9d or xe2x80x9csplicesxe2x80x9d) for the joinder of cable trays in cable tray systems wherein cable (or bundles thereof), including electrical cable or conduit, data transmission cable and the like, is strung.
The invention is especially directed to a junction for interconnection of convergent cable trays in a cable tray system wherein, in the stringing of the cable (or bundles thereof) in the trays, the cable may be pulled around from one tray to another tray at an angle to the one tray.
Reference may be had to Rinderer U.S. Pat. No. 5,782,439 issued Jul. 21, 1998 entitled Support System for Transmission Lines and Cable and to Rinderer U.S. Pat. No. 5,816,542 issued Oct. 6, 1998 entitled Support System for Data Transmission Lines for a showing of cable tray systems such as may be encountered in the field involving an arrangement of trays in which a junction of this invention may be used, as well as a showing of certain types of trays such as may be encountered. Reference may also be made to Rinderer U.S. Pat. No. 5,580,014 issued Dec. 3, 1996 entitled Ladder-Type Cable Tray for a showing of another type of cable tray such as may be encountered in such systems. These three patents are incorporated herein by reference.
Avoiding damage to cable in being pulled around from one tray to another at an angle thereto (usually a right angle), and thus subjected to bending, has been a problem, particularly with regard to data transmission cable, sharp bending of the latter being apt to adversely affect its data transmission capability. Compounding the problem, cable tray systems involving different types of cable trays, different sizes of cable trays, and different arrangements of trays may be encountered.
Among the several objects of the invention may be noted the provision of an improved junction for joinder of cable trays; the provision of such a junction which is adapted as supplied and without requiring extras or taking special steps to enable pulling cable around from one tray to another in a manner avoiding damage to the cable (e.g., in the case of data transmission cable, avoiding distortion of the quality of the data transmissability thereof); the provision of such a junction for joinder of cable trays in different configurations, particularly in L-formation, T-formation or cruciform formation; the provision of such a junction which is relatively economical to manufacture and convenient and economical to install; the provision of such a junction applicable to cable tray systems having trays of different widths and heights; and the provision of a juncture for multi-level trays.
In one aspect, a junction of this invention for the joinder of convergent cable trays comprises a panel for interconnection of the trays with one face of the panel facing upwardly thereby constituting its upper face, and at least one cable guide extending up from said upper face of the panel having a curved surface for guiding cable as it is pulled around from one tray to another. The curvature of this surface is such as to enable the bending of the cable as it is pulled around the curved surface while preserving the integrity of the cable. The guide is removably attached to the panel.
One junction of this invention is adapted for connection of two cable trays in L-formation, three cable trays in T-formation, or four cable trays in cruciform formation. The junction comprises a plate for interconnection of two, three or four trays with one face of the plate facing upwardly thereby constituting its upper face. The plate has a plurality of sides, a plurality of corners, and a plurality of cable guides extending up from the upper face of the plate, adjacent the corners. Each of the guides has a curved surface for guiding cable as it is pulled around from one tray to another at right angles thereto, the curvature of the curved surface being such as to enable the bending of the cable as it is pulled around the curved surface while preserving the integrity of the cable.
Another aspect of the present invention is directed to a junction system for the joinder of cable trays each comprising a rail having supports for supporting cable at different levels. The junction system includes a plurality of junctions, each comprising a plate for interconnection of two, three or four cable trays with one face of the plate facing upwardly thereby constituting its upper face. The plate has a plurality of sides, a plurality of corners, and a plurality of cable guides extending up from the upper face of the plate, adjacent the corners. Each of the guides has a curved surface for guiding cable as it is pulled around from one tray to another at right angles thereto, the curvature of the curved surface being such as to enable the bending of the cable as it is pulled around said curved surface while preserving the integrity of the cable. The upper faces of the plates of the junctions are generally in planes at different levels corresponding to the different levels of the cable.
The present invention also features a junction for connection of two cable trays in L-formation, three cable trays in T-formation, or four cable trays in cruciform formation. The junction comprises a plate for interconnection of two, three or four trays with one face of the plate facing upwardly thereby constituting its upper face. The plate has a plurality of sides, a plurality of corners, and a plurality of cable guides extending up from the upper face of the plate, adjacent the corners. Each cable guide is removably fastened on the plate by fasteners extending up through preformed holes in the plate arranged in a predetermined pattern.
In another aspect, the junction has four cable guides extending up from the upper face of the plate, one adjacent each corner, and each cable guide has a top retainer extending inward with respect to the plate for confining cable thereto.
Another feature of the junction is that the cable guides are removably fastened on a plate by fasteners extending up through holes in a predetermined pattern. The plate has sets of preformed holes each in the aforesaid pattern along each of the sides for fastening one or more of the guides on the plate in position spaced inward from a corner.
In still another embodiment, the plate has four sides, four corners, and four cable guides extending up from the upper face of the plate, one adjacent each corner. The guide is formed for connection to selected pairs thereof of one type of cable tray, and the plate is formed on each side thereof for connection of other types of cable tray.
The cable guides of the junctions of the present invention are preferably about 1-6 inches high. Also, the guides of a particular junction are of different height to accommodate cable tray of different sizes.
Another embodiment of the present invention involves a junction for connection of two or more converging cable trays. The junction comprises a panel having an upper face, a plurality of sides, a plurality of corners, a plurality of cable guides extending up from the upper face adjacent said corners, and a cover adapted to be removably fastened to the cable guides in a covering position overlying the panel and spaced therefrom. The cable guides have cover fastener openings therein for receiving fasteners to removably fasten the cover in said covering position.
In an additional embodiment, a junction of this invention comprises a panel having an upper face, a plurality of sides, a plurality of corners, and a plurality of cable guides extending up from the upper face adjacent the corners. The cable guides have accessory fastener openings therein for releasably fastening accessories to the cable guides.
Other objects and features will be in part apparent and in part pointed out hereinafter.